Foam is the aggregation of gases dispersed in solid polymers. Foam has the advantages of light weight, heat insulation, cushioning,EPE Foam Insulation insulation, corrosion resistance and low price. Therefore, in the daily necessities, packaging, industry, agriculture, transportation, military industry, aerospace industry is widely used.
The most common foam on the market is polyurethane (PUR), polystyrene (PS), polyvinyl chloride (PVC), polyethylene (PE), phenolic resin (PF) and polypropylene (PP).
The US market in recent years, the demand for foam to 4.2% annual rate of sustained growth; China since the 20th century, 90 years since the development of foam is very rapid, of which the main varieties are PS, PE, PUR three categories. But the above three types of materials have some limitations. Performance is as follows:
◆ Polyvinyl chloride (PS) used in the process of foaming HCFC compounds, will destroy the atmospheric ozone layer, the degradation of its products to the environment and cause "white pollution", so the United Nations Environmental Protection Organization decided to stop using the PS foam products in 2005 The According to the National Bill on China's Ozone Depleting Substances,EPE Foam Insulation China has determined that the CFCs used in foam production will be completely banned by December 31, 2005.
◆ Polyurethane foam sheet in the foam process there is harmful to the human body of isocyanate residues, and the foam material can not be recycled.
◆ The maximum operating temperature of the cross-linked polyethylene foam is 80 ° C. Similarly, the polystyrene foam is heated to its softening deformation at its glass transition temperature of 105 ° C.
EPP is a new type of high performance compressive cushioning insulation material with excellent physical properties, stable chemical properties and easy recovery. It is mainly used in IT packaging, communication equipment and automobile.
EPP and EPS material compared to a big difference is: EPS material to its own structure to achieve damage to the buffer effect, and EPP material through the material shrinkage and expansion,EPE Foam Insulation absorption and release of energy to achieve the effect of compression buffer. After repeated external forces, EPS material compression cushioning effect will be reduced, while the EPP material is very small. Therefore, it should be said that EPP materials compared to EPS materials, the compression buffer effect is more excellent.
1.EPP production process
Polypropylene foam beads (EPP) to PP as the main raw material, the use of physical foam technology made of foam beads. Mainly used for mold sintering molding for a variety of shapes and sizes for use in different occasions. Polypropylene foam beads made with polypropylene foamed beads and polypropylene foamed pellets are sintered with polypropylene foam products, which are used in many popular properties such as EPS and EPE. We first through the picture simple description EPP production process:
1) First, through a specific ratio, get color diversification of PP particles.
2) by foaming and other treatment, to be 5-60 times the foam PP particles, as shown above 60 times the white EPP.
3) The product is manufactured by heating the particles in 2 with steam to obtain the product.
2. What are the advantages of EPP compared to other foams?
◆ polypropylene (PP) is better than polyethylene (PE)
PP bending modulus of about 1.52Gpa, PE is only 207MGpa, chemical resistance and PE similar. In Japan, Furu Electric's Ace-type PP foam material, for example,EPE Foam Insulation its mechanical properties such as tensile strength and tear strength in the highest level of foam compression strength is lower than the hard PUR and foam PS, but higher than the soft PUR , Both with moderate compressive strength.
◆ Polypropylene has a high heat distortion temperature, can be used in the field of high temperatur
Foam polypropylene is usually resistant to 130 ° C, which is much higher than the maximum use temperature of polyethylene foam. Foaming PP is a closed cell structure as foamed PE, so its thermal conductivity is not affected by moisture and is lower than foamed PE,EPE Foam Insulation with significant heat insulation and therefore can be used as a high-grade insulation The
◆ good low temperature characteristics
EPP products exhibit good performance even at -30 ° C.
◆ high energy absorption
Because EPP products have a special cell structure, which through the bubble in the gas stagnation and compression to absorb the escape energy, with excellent compressive properties. Widely used in automotive bumper energy handling systems and other anti-collision energy absorption components.